MAPK-pathway inhibition mediates inflammatory reprogramming and sensitizes tumors to targeted activation of innate...

Area of Science:

• Oncology
• Immunology
• Molecular Biology

Background:

• Kinase inhibitors are crucial for treating oncogene-driven cancers but can lead to treatment resistance and tumor relapse.
• Understanding the mechanisms of resistance and identifying strategies to overcome it are critical for improving patient outcomes.

Purpose of the Study:

• To investigate the molecular mechanisms underlying treatment resistance in cancer cells during kinase inhibitor therapy.
• To identify novel therapeutic strategies that can synergize with kinase inhibitors to overcome resistance and enhance anti-tumor responses.

Main Methods:

• Transcriptomic and functional genomics analyses were performed on cells and tumors persisting during kinase inhibitor treatment.
• Innate immunity sensor RIG-I activation using agonist IVT4 was studied in combination with kinase inhibition.
• Experiments were conducted in humanized lung cancer xenografts and a syngeneic Egfr-driven lung cancer model.

Main Results:

• A conserved MAPK/IRF1-mediated inflammatory response was identified in tumors undergoing stemness and senescence reprogramming.
• Activation of RIG-I by IVT4 induced interferon and pro-apoptotic responses, synergizing with kinase inhibitors.
• This combination therapy led to reduced exhausted CD8+ T cells and significant tumor shrinkage in preclinical models.

Conclusions:

• The study reveals a mechanism of MAPK/IRF1-mediated reprogramming that contributes to resistance against kinase inhibitors.
• Activating RIG-I presents a promising strategy to overcome targeted therapy resistance in genetically defined cancers.
• Understanding these mechanisms may help prolong the efficacy of targeted drugs in cancer patients.